BriaCell Presents Phase 3 Clinical Biomarker Data at ESMO 2025

PHILADELPHIA and VANCOUVER, British Columbia, Oct. 20, 2025 (GLOBE NEWSWIRE) -- BriaCell Therapeutics Corp. (Nasdaq: BCTX, BCTXW, BCTXZ) (TSX: BCT) (“BriaCell” or the “Company”), a clinical-stage biotechnology company that develops novel immunotherapies to transform cancer care, announces encouraging clinical biomarker data in its ongoing pivotal Phase 3 study of Bria-IMT plus an immune check point inhibitor (CPI) in metastatic breast cancer. The findings are being presented in BriaCell’s poster presentation at the European Society for Medical Oncology (ESMO) Congress 2025 Annual Meeting taking place October 17 – 21, 2025 in Berlin, Germany. The Phase 3 data shown is for all patients evaluated regardless of treatment assignment (i.e. is blinded).

“We are encouraged by the early constructive clinical biomarker data which could allow us to predict clinical and survival outcomes in our patients and would help guide treatment decisions for metastatic breast cancer patients with limited options,” stated Dr. William V. Williams, BriaCell’s President and CEO.

In BriaCell’s pivotal Phase 3 study of Bria-IMT plus an immune check point inhibitor (CPI) in metastatic breast cancer, patients are randomized 1:1:1 to Bria-IMT + CPI, Treatment of Physician’s Choice, or Bria-IMT monotherapy. As of the time of the poster submission, pooled data was available in 113 patients, with a median of 6 prior lines of treatment (2–13). Evaluable only pertains to imaging. All 113 are evaluated for safety, PFS, etc.

As reported in the Phase 2 study, Neutrophil to Lymphocyte Ratio (NLR) continues to be a potential biomarker of clinical benefit as progression free survival (PFS) was significantly higher in patients with NLR of 0.7 – 2.3 (4.5 months) vs those with NLR < 0.7 or > 2.3 (2.5 months) {(HR) of 0.5 (95% CI 0.3–0.8, p=0.005)}.

In the Phase 3 study, PFS data comparing BriaCell’s Bria-IMT combination regimen versus those treated with physician’s choice remains blinded at this time. Bria-IMT has been well tolerated in the Phase 3 study with no treatment-related discontinuations due to adverse events (AEs). The most common AEs are minor, including fatigue, anemia, and nausea.

BriaCell’s pivotal Phase 3 study of Bria-IMT plus an immune check point inhibitor (CPI) in metastatic breast cancer is ongoing.

Interim data will be analyzed once 144 patient events (deaths) occur, comparing the overall survival (OS) in patients treated with the Bria-IMT combination regimen versus those treated with physician’s choice as the primary endpoint. Positive results of the pivotal Phase 3 study could result in full approval and marketing authorization for Bria-IMT in MBC patients.BriaCell reported positive Phase 2 survival data in a similar MBC patient population treated with the same Bria-IMT combination regimen. The Bria-IMT combination regimen has received FDA Fast Track designation.

For additional information on BriaCell’s pivotal Phase 3 study of Bria-IMT and an immune check point inhibitor in metastatic breast cancer, please visit ClinicalTrials.govNCT06072612.

A copy of the poster presentation is posted onhttps://briacell.com/scientific-publications/.

BriaCell is a clinical-stage biotechnology company that develops novel immunotherapies to transform cancer care. More information is available athttps://briacell.com/.

This press release contains “forward-looking statements” that are subject to substantial risks and uncertainties. All statements, other than statements of historical fact, contained in this press release are forward-looking statements. Forward-looking statements contained in this press release may be identified by the use of words such as “anticipate,” “believe,” “contemplate,” “could,” “estimate,” “expect,” “intend,” “seek,” “may,” “might,” “plan,” “potential,” “predict,” “project,” “target,” “aim,” “should,” “will,” “would,” or the negative of these words or other similar expressions, although not all forward-looking statements contain these words. Forward-looking statements, including: BriaCell's plans to present clinical data presentations at the ESMO Congress 2025, and the contents of all such presentations; BriaCell's statements regarding early constructive clinical biomarker data allowing the Company to predict clinical and survival outcomes and guide treatment decisions for metastatic breast cancer patients; and the Company's anticipated timing of analysis of interim data are based on BriaCell’s current expectations and are subject to inherent uncertainties, risks, and assumptions that are difficult to predict. Further, certain forward-looking statements are based on assumptions as to future events that may not prove to be accurate. These and other risks and uncertainties are described more fully under the heading “Risks and Uncertainties” in the Company's most recent Management’s Discussion and Analysis, under the heading "Risk Factors" in the Company's most recent Annual Information Form, and under “Risks and Uncertainties” in the Company's other filings with the Canadian securities regulatory authorities and the U.S. Securities and Exchange Commission, all of which are available under the Company's profiles on SEDAR+ atwww.sedarplus.caand on EDGAR atwww.sec.gov. Forward-looking statements contained in this announcement are made as of this date, and BriaCell Therapeutics Corp. undertakes no duty to update such information except as required under applicable law.

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